The present invention relates to a twist-beam axle for the rear suspension of a motor vehicle, as well as a method for the production of such a twist-beam axle.
It is known in the automotive field the use of rear suspensions in which the two rear wheels are interconnected by means of a twist-beam axle comprising basically a central cross-member compliant to torsion, which extends substantially transversely and a pair of rigid trailing arms, attached to the ends of the cross-member, which support the rear wheels and provide the articulation of the axle to the vehicle body.
According to the prior art, the trailing arms of the twist-beam axle are formed as elongated integral bodies, for example of tubular shape, which are securely connected to the cross-member, for example by welding. Alternatively, a pair of trailing half-arms, that is, a front half-arm and a rear half-arm, respectively, may be provided for instead of a single trailing arm, wherein usually the rear half-arm is formed as a single piece with the cross-member whereas the front one is fixed to the cross-member, for example by welding. These known arrangements, which require a welded joint to be provided between the trailing arms, or the half-arms, and the cross-member, require a high dimensional and shape precision in the welding zones, in order to ensure the correct relative positioning of the parts to be connected and the strength of the welded connection.
A twist-beam axle for the rear suspension of a motor vehicle, including a central cross-member and a pair of trailing arms fixed to respective side end portions of the cross-member (11) is known from EP-A-0 743 205. According to this known solution, each trailing arm comprises a pair of transversely inner half-shells, that is, a front half-shell and a rear half-shell, respectively, which are formed by prolongations of the respective end portion of the cross member, and a transversely outer half-shell securely connected to the pair of transversely inner half-shells so as to form therewith a structure having a closed cross-section.